A brief introduction to UML Dynamic Model diagram

UML Dynamic Model diagram describes various aspects of system dynamic behavior, including use case diagram, sequence diagram, collaboration diagram, activity diagram and state diagram. Here is a brief description of each diagram:

use case diagram

A use case diagram describes some kind of connection between the performer outside the system and the use case provided by the system. A use case refers to a description of the functionality provided by the system. The performer is the person using the use case or the external system, and the links between them describe "who uses which use case". The use case diagram focuses on describing what the system needs to provide from the perspective of the external performer of the system and indicates who the performer is. In a use case diagram, the ellipse represents the use case, and the villain represents the performer. Shown as a general user into a system of use case diagram, which describes when the ordinary user into the system, "ordinary user" as the performer, it has password modification, data modification, order query, product search and other 4 use cases.

sequence Diagram

Sequence diagrams, also known as time series diagrams, sequence diagrams, are used to describe dynamic collaborative relationships between several objects. A sequence diagram consists of a set of objects, each with a vertical line representing the timeline, called a lifeline. A horizontal arrow that points to the lifeline of another object from the lifeline of one object represents the message. Sequence diagrams are the process of describing how these objects exchange messages with each other over time. As an example of a sequence diagram of fund transfer between banks, through the Central inter-bank transfer, describe the interaction between bank A, center, bank b, through this model diagram, you can clearly understand the entire interaction process and the sequence of interactions.

Collaboration Diagram

As with sequence diagrams, collaboration diagrams are also used to describe dynamic collaboration relationships between objects in a system. The collaboration diagram focuses on describing the messaging relationships that exist between objects, rather than highlighting the chronological order in which these messages are sent. is a collaboration diagram corresponding to the above sequence diagram, the message arrows between objects indicate the flow of messages between them, and the labels on the message indicate the timing of the messages being sent.

State Diagram

A state diagram complements a class description to demonstrate the possible state of such an object and the transition of its state when certain events occur. Shows a state diagram of an elevator, a rounded rectangle that represents a state, an arrow that represents a transition of state, and an event that occurs next to a transfer. such as: When the elevator is in the rising state of the "arrival" event occurs, the elevator to idle state.

Activity Chart

An activity diagram is a special state diagram that describes the execution flow of activities to be performed in an operation. At the same time, it is often used to describe the process of a use case or some kind of interaction process. Shown is an activity diagram of a print server. The description of the model diagram gives you an idea of what activities and sequence of activities are required to perform the print function. The rounded rectangle in the figure represents the activity, and the activity diagram is made up of some activities. When an activity has finished executing, the control moves along the arrow to the next activity until the end.

A brief introduction to UML Dynamic Model diagram